<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>示例3</title>
    <script src="jquery.js" type="text/javascript"></script>
    <script>
        $(document).ready(function (){
            alert("hello")
        })
    </script>
</head>
<body>

</body>
</html>